The present invention relates to pharmaceutical compositions, and particularly pharmaceutical compositions incorporating compounds that are capable of affecting nicotinic cholinergic receptors. More particularly, the present invention relates to compounds capable of acting to inhibit function of certain nicotinic cholinergic receptors, and hence acting as antagonists at certain specific nicotinic receptor subtypes. The present invention also relates to methods for treating a wide variety of conditions and disorders, including conditions and disorders associated with dysfunction of the central and autonomic nervous systems.
Nicotine has been proposed to have a number of pharmacological effects. See, for example, Pullan et al. N. Engl. J. Med. 330:811-815 (1994). Certain of those effects may be related to effects upon neurotransmitter release. See for example, Sjak-shie et al., Brain Res. 624:295 (1993), where neuroprotective effects of nicotine are proposed. Release of acetylcholine and dopamine by neurons upon administration of nicotine has been reported by Rowell et al., J. Neurochem. 43:1593 (1984); Rapier et al., J. Neurochem. 50:1123 (1988); Sandor et al., Brain Res. 567:313 (1991) and Vizi, Br. J. Pharmacol. 47:765 (1973). Release of norepinephrine by neurons upon administration of nicotine has been reported by Hall et al., Biochem. Pharmacol. 21:1829 (1972). Release of serotonin by neurons upon administration of nicotine has been reported by Hery et al., Arch. Int. Pharmacodyn. Ther. 296:91 (1977). Release of glutamate by neurons upon administration of nicotine has been reported by Toth et al., Neurochem Res. 17:265 (1992). In addition, nicotine reportedly potentiates the pharmacological behavior of certain pharmaceutical compositions used for the treatment of certain disorders. See, Sanberg et al., Pharmacol. Biochem. & Behavior 46:303 (1993); Harsing et al., J. Neurochem. 59:48 (1993) and Hughes, Proceedings from Intl. Symp. Nic. S40 (1994). Furthermore, various other beneficial pharmacological effects of nicotine have been proposed. See, Decina et al., Biol. Psychiatry 28:502 (1990); Wagner et al., Pharmacopsychiatry 21:301 (1988); Pomerleau et al., Addictive Behaviors 9:265 (1984); Onaivi et al., Life Sci. 54(3):193 (1994); Tripathi et al., JPET221: 91-96 (1982); and Hamon, Trends in Pharmacol. Res. 15:36.
Various nicotinic compounds have been reported as being useful for treating a wide variety of conditions and disorders. See, for example, Williams et al. DN&P 7(4):205-227 (1994), Arneric et al., CNS Drug Rev. 1(1):1-26 (1995), Americ et al., Exp. Opin. Invest. Drugs 5(1):79-100 (1996), Bencherif et al., JPET 279:1413 (1996), Lippiello et al., JPET 279:1422 (1996), Damaj et al., Neuroscience (1997), Holladay et al., J. Med. Chem. 40(28): 4169-4194 (1997), Bannon et al., Science 279: 77-80 (1998), PCT WO 94/08992, PCT WO 96/31475, and U.S. Pat. No. 5,583,140 to Bencherif et al., U.S. Pat. No. 5,597,919 to Dull et al., and U.S. Pat. No. 5,604,231 to Smith et al. Nicotinic compounds are reported as being particularly useful for treating a wide variety of Central Nervous System (CNS) disorders.
CNS disorders are a type of neurological disorder. CNS disorders can be drug induced; can be attributed to genetic predisposition, infection or trauma; or can be of unknown etiology. CNS disorders comprise neuropsychiatric disorders, neurological diseases and mental illnesses; and include neurodegenerative diseases, behavioral disorders, cognitive disorders and cognitive affective disorders. There are several CNS disorders whose clinical manifestations have been attributed to CNS dysfunction (i.e., disorders resulting from inappropriate levels of neurotransmitter release, inappropriate properties of neurotransmitter receptors, and/or inappropriate interaction between neurotransmitters and neurotransmitter receptors). Several CNS disorders can be attributed to a cholinergic abnormality, a dopaminergic abnormality, an adrenergic abnormality and/or a serotonergic abnormality. CNS disorders of relatively common occurrence include presenile dementia (early onset Alzheimer's disease), senile dementia (dementia of the Alzheimer's type), Parkinsonism including Parkinson's disease, Huntington's chorea, tardive dyskinesia, hyperkinesia, mania, attention deficit disorder, anxiety, dyslexia, schizophrenia, Tourette's syndrome and neuroendocrine disorders (e.g., obesity, bulemia and diabetes insipidus).
Nicotinic receptor antagonists have been used for the treatment of certain disorders. For example, mecamylamine has been marketed as Inversine by Merck & Co. Inc. as an antihypertensive agent; and trimethaphan has been marketed as Arfonad by Roche Laboratories as a vasodepressor agent. See, Goodman and Gilman's The Pharmacological Basis of Therapeutics, 6.sup.th Ed p. 217 (1980). Nicotinic receptors have been implicated in convulsions, such as those that occur as a result of autosomal dominant nocturnal frontal lobe epilepsy. See, Steinlein et al., Nat. Genet. 11: 201-203 (1996). Nicotinic antagonists have been reported to inhibit viral infection. For example, nicotinic antagonists have been reported to inhibit the infection of dorsal root ganglion neurons by the rabies virus. See, Castellanos et al., Neurosci. Lett. 229: 198-200 (1997). Other uses for nicotinic antagonists have been proposed. See, for example, Popik et al., JPET 275: 753-760 (1995) and Rose et al., Clin. Pharm. Ther. 56(1): 86-9 (1994).
Derivatives of adamantane have been recognized as being antagonists at certain receptor subtypes. See, for example, Antonov et al., Mol. Pharmacol., 47(3): 558-567 (1995) and Becker et al., Bioorg. Med. Chem. Let. 7(14): 1887-1890 (1997). Derivatives of adamantane also have been shown to exhibit antiviral properties. See, for example, Fytas et al., Bioorg. Med. Chem. Let. 7(17): 2149-2154 (1997); Skwarski et al., Acta Poloniae Pharmaceutica, 45: 391-394 (1988); Kreutzberger et al,, Archiv der Pharmazie, 308: 748-754 (1975); Pellicciari et al., Arzneimittel-Forshung 30: 2103-2105 (1980); Danilenko et al., Farma. Zhurnal, 31: 36-40 (1976); and Beare et al., Lancet 1: 1039-1040 (1972). Derivatives of adamantane also have been shown to exhibit anti-bacterial properties. See, for example, Garoufalias et al., Annales Pharmaceutiques Francaises, 46: 97-104 (1988). Derivatives of adamantanes also have been reported as inhibitors of convulsions. See, Antonov et al., Mol. Pharmacol., 47(3): 558-567 (1995). Derivatives of adamantane also have been proposed for the treatment of type II diabetes. See, Campbell, Pharmacy Times 53: 32-37, 39-40 (1987). Derivatives of adamantane also have been proposed to have a marked anorectic effect in mice. See, Farmazo-Edizione Scientifica 34: 1029-1038 (1979). Derivatives of adamantane also have been proposed be effective in the prevention of catalepsy in animal models. See, Vikhlyaev et al., Pharm. Chem. J. 14: 185-188 (1981).
It would be desirable to provide a useful method for the prevention and treatment of a conditon or disorder by administering a nicotinic compound to a patient susceptible to or suffering from such a disorder. It would be highly beneficial to provide individuals suffering from certain disorders with interruption of the symptoms of those disorders by the administration of a pharmaceutical composition containing an active ingredient having nicotinic pharmacology and providing a beneficial effect, but which does not provide any significant associated side effects (e.g., increased heart rate and blood pressure attendant with interaction of that compound with cardiovascular sites). It would be highly desirable to provide a pharmaceutical composition incorporating a compound that interacts with nicotinic receptors, but which composition does not significantly effect those receptor subtypes which have the potential to induce undesirable side effects (e.g., appreciable pressor cardiovascular effects and appreciable activity at skeletal muscle sites).